<?php
$db=new PDO('mysql:host=localhost;dbname=db', 'root', '12qwas');
$result=$db->query("select cy as 成语, first 首字 from chengyu limit 2");
foreach($result as $row){
    //print_r($row);
    echo "{$row[0]}-------{$row['首字']}\n";
}
